Fertilization techniques such as artificial insemination and in vitro fertilization techniques have been conducted in attempt to increase the fertility rates of livestock. Furthermore, effective pre-selection of sex has been accomplished in many species of livestock following the development of safe and reliable methods of sorting, generally, or specifically separating sperm cells into enriched X chromosome bearing and Y chromosome bearing populations. Separation of X chromosome bearing sperm cells from Y chromosome bearing sperm cells, as well as collection, handling, sorting, separation, storage, transportation, use, fertilization, or insemination techniques, or sperm cell and semen processing generally, can be accomplished as disclosed herein and as disclosed by various patent applications, for example: PCT/US99/17165; PCT/US01/45023; PCT/US01/15150; PCT/US98/27909; PCT/US01/45237, PCT/US01/18879, PCT/US00/30155, PCT/US01/02304, U.S. Pat. Nos. 6,071,689, 6,372,422, U.S. divisional application No. 10/081,955, U.S. provisional application No. 60/400,486, and U.S. provisional application No. 60/400,971, each included in Exhibit A attached, and each hereby incorporated by reference herein.
Although the various devices and methods of sperm cell processing, generally, and the collection, handling, separation, storage, transportation, usage, fertilization, and insemination of sperm cells have been improved over the past several years, significant problems remain with respect to maintaining sperm quality, such as viability, motility, functionality, and preservation and stimulation relative to such techniques, especially with regard to artificial insemination (in vivo) and in vitro fertilization (IVF) procedures. One potential consequence is the reduction in fertility rates. Sperm quality, such as the viability of sperm separated into enriched X-chromosome bearing and Y-chromosome bearing populations could be compared directly in-vitro (for example, in conjunction with IVF procedures) and in-vivo (for example, in conjunction with artificial insemination procedures), is generally reduced during traditional sperm cell processing. More generally, traditional processing techniques addressing sperm viability, motility, functionality, preservation, stimulation, fertilization, and insemination may have not yielded preferred fertility rates, insemination rates, fertilization rates, or sperm quality, generally.
As one example of traditional sperm processing, techniques of sperm sorting for the breeding of mammals may be limited, for example, with regard to sperm cell quality, such as sperm cell viability, and fertility rates, in circumstances wherein the sorter apparatus is a relatively long distance from the males or when the sorter apparatus is a relatively long distance from the receiving females to be inseminated or otherwise fertilized with processed sperm. Some of the techniques incorporated by reference may achieve to some degree sperm cell viability, motility, or functionality, and desirable fertility rates, while addressing, for example, sperm preservation during transportation to the sorter apparatus. However, further techniques achieving sufficient sperm cell quality, such as viability, motility, functionality, stimulation, and preservation, and maintained or enhanced fertility rates, insemination rates, fertilization rates, may be desirable, especially for any one or a combination of various sperm processing steps, such as, for example, collection, handling, separation, storage, transportation, usage, fertilization, or insemination of semen or sperm cells, especially the preservation of the sorted sperm cells from the sorter apparatus to the site of fertilization (potentially via collected individual samples or “straws”), or at any other stage of sperm processing.
As another example of the limitations of traditional sperm processing, traditional processing techniques may be limited with regard to sperm cell quality, generally, such as sperm cell viability, motility, functionality, stimulation, and preservation, as well as fertility rates, insemination rates, fertilization rates, due to the type and the extent processing involved. Known processing techniques such as preservation or sorting, for example, may degrade sperm quality, and further reduce fertility rates, insemination rates, and fertilization rates. The degradation of sperm quality and/or the reduction of fertility rates, insemination rates, and fertilization rates may have previously proven problematic in circumstances that may have required further steps of sperm cell preservation, such as in circumstances wherein the sorter apparatus is a relatively long distance from the males or when the sorter apparatus is a relatively long distance from the receiving females to be inseminated or otherwise fertilized with processed sperm.
It may have been traditionally understood that additional processing steps in the processing of sperm cells or semen having a concentration of sperm cells would degrade sperm quality and reduce fertility rates, insemination rates, and fertilization rates to such an extent that additional processing steps, generally, would be avoided. Specifically, it may also have been traditionally understood that processing steps such as preservation, specifically cryopreservation, and sorting might be too damaging to the sperm cells, especially in processing sequences incorporating both cryopreservation and sorting. Furthermore, it may have even been suggested and taught in traditional methods that preservation of sperm, such as cryopreservation, provided after previous processing steps so as to preserve the sperm for later procedures, such as for in vivo or in vitro techniques, could not be accomplished without compromising the sperm cells and the technique itself to such a degree that the results of the later procedures would be detrimentally affected. Accordingly, such concerns may have even been demonstrated in traditional sperm cell processing procedures, teaching away from subsequent processing steps such as sorting and cryopreservation, or processing steps incorporating multiple cryopreservation steps.